The Butterfly Nebula

The Butterfly Nebula in Cygnus is part of a much larger region of nebulosity
surrounding the bright star Sadr (to the right edge of this image), the
center star of the Northern Cross. For reference, the butterfly nebula
is contained within the Gamma Cygni Nebula, which can be seen
here in my gallery.

Narrowband

In this false-colour image Sulfur-II is mapped to red, Hydrogen-Alpha is
mapped to green, and Oxygen-III is mapped to blue.